Example:
Set string length to 4 and maximium value of numbers in string to 4.
(Press St and M and L
respectively to adjust.)

Press Mx to start timer and create string to guess (not shown of course,
but let's assume that the string '2144' is created).

Press # to put '1111' in tos.
Press ? to compute guess.
Let's say that rpn answers '1111.1'. This means that one number in the
guess is correct.

Press # to put '2222' in tos. Press the leftmost - to change to '1222'.
Press ? to compute guess.
Let's say that rpn answers '1222.02'. This means that two numbers are in
the hidden string but in other locations.

Press input field to repeat guess, i.e. duplicate '2133.2'. Press + in
third and fourth position
to change to '2144.2'.
Press ? to compute guess (fractional part of guess doesn't matter).
Rpn answers 'Correct!' and '2144.4'. You got it!

You can now inspect number of guesses, guessing time and score. If you
made a high score you will be told.

IMPORTANT WARNING:
Before using the application for the first time, suitable values for
string length and maximum
value of numbers should be chosen! Otherwise the application may go into
an endless loop when
computing a guess!

Follow this routine before application is used for the first time:
Press St for setting parameters.
Press M for adjusting maximum value of numbers in string. Use arrows to
adjust to value between 1 and 9.
Press L for adjusting length of string. Use arrows to adjust to value
between 1 and 9.

Remark:
Values for time and score will only be correct after guessing the right
string.